A pants-type disposable diaper which has a waist opening at an upper end and a pair of leg openings on a lower part is conventionally used as one type of absorbent product for receiving excrement from a wearer. For example, in Japanese Patent Publication No. 3051733 (Document 1), disclosed is a disposable underpants where edges of leg openings in a front part are formed by cutting deeply in comparison with edges of leg openings in a rear part.
In Japanese Patent Publication No. 3916878 (Document 2), a method of manufacturing a pants-type disposable diaper is disclosed. In the method of Document 2, a pair of leg elastic members is bonded, in a sine wave form, on strip-like web, and the web is cut between the pair of leg elastic members to form two half webs. Subsequently, the two half webs are brought away from each other, and a plurality of absorbent pads are located between these half webs to be bonded thereon. These absorbent pads are half-folded to lay the two half webs on each other. The two half webs are bonded to each other at bonding positions between the plurality of absorbent pads and the half webs are cut at the bonding positions to form disposable diapers.
On the other hand, in International Publication No. WO 2007/145130 (Document 3), disclosed is a belt-type disposable diaper where left and right side portions of a front part and left and right side portions of a rear part are connected with fastening tapes to be worn. The disposable diaper of Document 3 is manufactured by a manufacturing method similar to the method of Document 2. In the manufacturing method of Document 3, steps of Document 2 to lay the two half webs on each other and bond them between the plurality of absorbent pads are omitted.
In the disposable underpants of Document 1, in a cover sheet bonded on an outer surface of an absorbent body, as distance in a left-right direction from the absorbent body increases, a lower edge of the rear part to be positioned on the back side of a wearer (i.e., the lower edge including parts of edges of the leg openings) goes toward its upper edge (i.e., the upper edge included in the edge of the waist opening). Ditto with the disposable diapers of Document 2 and Document 3, out of two cover sheets to which end portions of the absorbent pad are bonded, a lower edge of one cover sheet to be positioned on the back side of a wearer goes toward its upper edge as distance in the left-right direction from the absorbent body increases.
Thus, in the disposable diapers of Document 1 to Document 3, it is difficult to fully wrap the hips of the wearer with the cover sheet. Therefore, lower portions of the hips (i.e., the neighborhoods of borders between the hips and thighs) are exposed at positions below the disposable diaper (i.e., the lower portions are not covered with the disposable diaper.) and there is a possibility that excrement leaks out to the positions.